u/Civil_Poem_8091

I am currently in class 10th choosing my subject, and I have decided to choose PCM as my subject because my school didn't have PCMB, although I love both biology and maths, getting them both in my school wasn't possible. So i have a question. If I pass Class 12th By PCM can I take NIOS to change my stream to PCB? If I do change my mind later on (which shouldn't happen I know) but still is it possible? If yes, then what are the criterias for it?